Sterile barrier assembly, mounting system, and method for coupling surgical components

ABSTRACT

A sterile barrier assembly, mounting system, and method for kinematically coupling first and second surgical components together through the sterile barrier assembly so that positioning is repeatable and deterministic.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and the benefit of U.S. ProvisionalPatent Application No. 62/118,737, filed on Feb. 20, 2015, the entirecontents of which is hereby incorporated by reference herein.

TECHNICAL FIELD

The present invention relates to a sterile barrier assembly, mountingsystem, and method for coupling surgical components through the sterilebarrier assembly.

BACKGROUND

Sterile barrier assemblies such as surgical drapes are known forestablishing barriers between surgical components during surgery. Forinstance, a surgical drape may be used to provide a barrier between arobotic arm and an end effector attached to the robotic arm. In surgery,the robotic arm is treated as being nonsterile, while the end effectoris sterile. The surgical drape creates a barrier between the robotic armand the end effector to prevent contamination of a sterile field inwhich the end effector is operating.

Typically, surgical drapes placed between the robotic arm and the endeffector have perforations or other openings through which differentconnections can be made between the robotic arm and the end effector,such as mechanical connections and/or electrical connections. Suchperforations are acceptable, so long as they are covered during thesurgery. If the end effector fails during the surgery and needs to bereplaced, or if a different end effector is desired, and theperforations become uncovered, standard operating room sterilityprotocol may dictate that the surgical drape requires replacement beforea different end effector can be installed. Removal of the surgical drapeand installation of a new surgical drape takes up valuable time, soreplacement is undesirable.

Other surgical drapes are not intentionally perforated, but instead arecompressed between the robotic arm and the end effector. Whencompressed, if the surgical drape is formed of thin plastic, unintendedrips or tears may occur. Even when the surgical drape does remainintact, positioning of the end effector on the robotic arm is impreciseas a result of the compressibility of the surgical drape. For example,the surgical drape may compress unequally. Further, a thick drape madeout of conventional draping materials could deflect under normal endeffector loads. Small deflections are magnified out to a tool centerpoint (TCP) of the end effector and can become intolerable due to errorsin positioning accuracy of the TCP.

Therefore, there is a need in the art for addressing one or more ofthese deficiencies.

SUMMARY

In one embodiment a sterile barrier assembly is provided forestablishing a barrier between first and second surgical componentsduring a surgery. The assembly includes a protective covering having aplurality of kinematic couplers. The kinematic couplers provide akinematic coupling between the first and second surgical componentsthrough the protective covering.

In another embodiment a mounting system for coupling first and secondsurgical components is provided. The system includes a first mountingportion for the first surgical component and a second mounting portionfor the second surgical component. The system also includes a protectivecovering having a plurality of kinematic couplers to kinematicallycouple the first and second mounting portions through the protectivecovering.

A method is provided in yet another embodiment for coupling first andsecond surgical components. The method includes placing a sterilebarrier assembly having a plurality of kinematic couplers on the firstsurgical component. The method further includes placing the secondsurgical component on the sterile barrier assembly. The method furtherincludes preloading a preload element to kinematically couple thesurgical components together via the plurality of kinematic couplersthrough the sterile barrier assembly.

One advantage of the sterile barrier assembly, mounting system, andmethod is the ability to kinematically couple the first surgicalcomponent to the second surgical component through the sterile barrierassembly so that positioning is repeatable and deterministic whilekeeping the sterile barrier assembly intact.

BRIEF DESCRIPTION OF THE DRAWINGS

Advantages of the present invention will be readily appreciated as thesame becomes better understood by reference to the following detaileddescription when considered in connection with the accompanying drawingswherein:

FIG. 1 is a perspective view of a robotic surgical system including amounting system and a sterile barrier assembly;

FIG. 2 is a perspective view of the mounting system;

FIG. 3 is a cross-sectional perspective view of the mounting system ofFIG. 2;

FIG. 4 is another cross-sectional perspective view of the mountingsystem of FIG. 2;

FIG. 5 is a front perspective view of a first mounting portion;

FIG. 6 is a front perspective view of a second mounting portion;

FIG. 7 is a front perspective view of a sterile barrier assembly;

FIG. 8 is a cross-sectional perspective view of the sterile barrierassembly;

FIG. 9 is a cross-sectional perspective view of the mounting system ofFIG. 2;

FIG. 10 is a cross-sectional perspective view of the first mountingportion of FIG. 5;

FIG. 11 is a cross-sectional perspective view of the first mountingportion of FIG. 5;

FIG. 12 is a cross-sectional perspective view of the second mountingportion of FIG. 6;

FIG. 13 is a perspective view of components of a preloading mechanism;

FIG. 14 is a perspective view of a catch associated with the secondmounting portion of FIG. 6;

FIG. 15 is a perspective view of a cam shaft of the preloadingmechanism;

FIG. 16 is a cross-sectional perspective view illustrating electricalconnections between the first and second mounting portions through thesterile barrier assembly;

FIG. 17 is a perspective view of an alternative mounting system;

FIG. 18 is a cross-sectional perspective view of the alternativemounting system of FIG. 17;

FIG. 19 is another cross-sectional perspective view of the alternativemounting system of FIG. 17;

FIG. 20 is a front perspective view of a first mounting portion;

FIG. 21 is a front perspective view of a second mounting portion;

FIG. 22 is a front perspective view of an alternative sterile barrierassembly;

FIG. 23 is a rear perspective view of the alternative sterile barrierassembly;

FIG. 24 is a cross-sectional perspective view of the alternative sterilebarrier assembly (without drape);

FIG. 25 is a cross-sectional perspective view of the alternative sterilebarrier assembly (without drape);

FIG. 26 is an exploded perspective view of the alternative sterilebarrier assembly (without drape);

FIG. 26A is a close-up view taken from FIG. 26;

FIG. 27 is a cross-sectional perspective view of the alternativemounting system of FIG. 17;

FIG. 28 is a perspective view of a load member;

FIG. 29 is a perspective view of a cam shaft;

FIG. 30 is a cross-sectional perspective view of the first mountingportion;

FIG. 31 is a cross-sectional perspective view of the second mountingportion; and

FIG. 32 illustrates the steps of mounting the alternative sterilebarrier assembly onto a robotic arm and an end effector.

FIG. 33 is another alternative barrier assembly.

FIG. 34 is a cross-sectional view of the alternative barrier assembly ofFIG. 33.

FIG. 35 is a close-up view of a drape of the alternative barrierassembly of FIG. 33.

FIG. 36 is a cross-sectional view of another alternative mounting systemincorporating the alternative barrier assembly of FIG. 33.

FIG. 37 is a perspective view of a back plate assembly of thealternative barrier assembly of FIG. 33.

FIGS. 38 and 39 are cross-sectional views of the alternative barrierassembly of FIG. 33 showing connection to a first mounting portion of arobot arm.

FIGS. 40 and 41 are cross-sectional views of the alternative barrierassembly of FIG. 33 showing connection to a second mounting portion ofan end effector.

FIGS. 42 and 43 are exploded views of components of a preloadingmechanism of the alternative barrier assembly of FIG. 33.

FIG. 44 is a partially exploded view of a lever of the alternativebarrier assembly of FIG. 33.

FIG. 45 is an illustration of the lever of FIG. 44 used to preload thealternative barrier assembly of FIG. 33.

FIG. 46 is an elevational view of components of an actuator used torelease the alternative barrier assembly of FIG. 33 from the firstmounting portion of the robot arm.

FIGS. 47A and 47B are illustrations of gross positioning features usedto align the alternative barrier assembly of FIG. 33 when mounting tothe first mounting portion.

DETAILED DESCRIPTION

Referring to FIGS. 1 and 2, a mounting system 20 is shown forkinematically coupling first and second surgical components using asterile barrier assembly 22. In one embodiment described herein, thefirst surgical component is a robotic arm R and the second surgicalcomponent is an end effector EE for the robotic arm R. It should beappreciated that the mounting system 20 can be employed to kinematicallycouple any surgical components using the sterile barrier assembly 22.

The robotic arm R includes a first mounting portion 24 and the endeffector EE includes a second mounting portion 26. The sterile barrierassembly 22 is located between the first and second mounting portions24, 26 to establish a barrier between the robotic arm R and the endeffector EE during surgery. This barrier separates the robotic arm Rfrom a sterile field S in which the end effector EE is operating. Duringsurgery, the robotic arm R is considered nonsterile and the barrierreduces the potential for migration of contaminants from the robotic armR into the sterile field S.

The mounting portions 24, 26 are kinematically coupled together usingthe sterile barrier assembly 22. Kinematic coupling provides a rigidconnection between the mounting portions 24, 26 so that positioningbetween the mounting portions 24, 26 can be deterministic andrepeatable. As a result of this rigid, deterministic and repeatableconnection, errors in positioning the end effector EE that may otherwisebe associated with a more flexible connection can be reduced.

Kinematic coupling exactly constrains the number of degrees of freedomthat are to be constrained, i.e., no degree of freedom isoverconstrained. For instance, in one embodiment there are six degreesof freedom between the mounting portions 24, 26, e.g., threetranslational and three rotational. Thus, kinematic coupling constrainsexactly those six degrees of freedom.

Referring to FIGS. 3 and 4, a plurality of kinematic couplers (alsoreferred to as kinematic elements) of the sterile barrier assembly 22are used to kinematically couple the mounting portions 24, 26. In theembodiment shown, the kinematic couplers are spherical balls 28. Duringuse, the balls 28 are seated in first and second pluralities ofreceptacles 30, 32, 34, 36, 38, 40 of the mounting portions 24, 26. Thereceptacles 30, 32, 34, 36, 38, 40 are sized and shaped to receive theballs 28. In the embodiment shown, the first mounting portion 24includes a first body 42 and a first cover plate 44 fixed to the firstbody 42. The first plurality of receptacles 30, 32, 34 are fixed in thefirst cover plate 44. The second mounting portion 26 includes a secondbody 46 and a second cover plate 48 fixed to the second body 46. Thesecond plurality of receptacles 36, 38, 40 are fixed in the second coverplate 48.

Referring to FIGS. 5 and 6, the first plurality of receptacles 30, 32,34 includes one receptacle 30 having a contact surface 50 with a conicalconfiguration (also referred to as a cone receptacle). Anotherreceptacle 32 has a pair of contact surfaces 52 provided by a V-shapedgroove (also referred to as a V-grooved receptacle). Yet anotherreceptacle 34 has a contact surface including a flat 54 (also referredto as a planar receptacle). The second plurality of receptacles 36, 38,40 includes three receptacles having contact surfaces 56 with conicalconfigurations (i.e., cone receptacles). Three balls 28 are capturedbetween corresponding, aligned pairs of the receptacles, i.e.,receptacle 30 to receptacle 36, receptacle 32 to receptacle 38, andreceptacle 34 to receptacle 40, as shown in FIGS. 3 and 4. The contactsurfaces 50, 52, 54, 56 of the receptacles 30, 32, 34, 36, 38, 40 act asconstraint surfaces for the kinematic coupling described herein.

The receptacles 30, 32, 34, 36, 38, 40 may be formed of steel or othersuitably rigid materials and may be separate components rigidlyconnected to the cover plates 44, 48 or may be integral with the coverplates 44, 48. The receptacles 30, 32, 34, 36, 38, 40 may be integratedinto the mounting portions 24, 26, in which case the receptacles 30, 32,34, 36, 38, 40 simply comprise constraint surfaces integral with themounting portions 24, 26 for securing the balls 28, or the receptacles30, 32, 34, 36, 38, 40 may otherwise be attached to the mountingportions 24, 26 in numerous ways via numerous structures.

When the mounting portions 24, 26 are brought together in approximatefinal orientation with the sterile barrier assembly 22 positionedtherebetween, the balls 28 of the sterile barrier assembly 22 self-seatinto the receptacles 30, 32, 34, 36, 38, 40. The cone receptacle,V-grooved receptacle, and planar receptacle of the first mountingportion 24 remove, three, two, and one degrees of freedom, respectively,via three, two, and one points of contact with the balls 28. Thus,exactly six degrees of freedom are constrained. In other embodiments,described further below, each of the first plurality of receptacles 30,32, 34 of the first mounting portion 24 may remove two degrees offreedom via two points of contact with the balls 28. In either of thesecases, exactly six degrees of freedom are constrained via exactly sixcontact points, e.g., one contact point for each degree of freedom.

Referring to FIGS. 7 and 8, the sterile barrier assembly 22 includes aprotective covering 58. The protective covering 58 includes an interface60 and a drape 62 attached to the interface 60. The drape 62 has aninterior surface and an exterior surface. The interior surface is placedadjacent to the robotic arm R during surgery. In the embodiment shownthe drape 62 is fitted to the robotic arm R to generally encompass therobotic arm R. The drape 62 is formed of at least one of polyethylene,polyurethane, and polycarbonate. The drape 62 may be attached to theinterface 60 by ultrasonic welding, tape, adhesive, or the like. Thedrape 62 is attached to the interface 60 so that no perforations arepresent, i.e., the drape forms a continuous barrier with the interface60.

In the embodiment shown, the interface 60 is formed of molded plasticmaterial. The interface 60 may be formed of rubber, silicone, urethane,or other suitable materials. The interface 60 includes a main wall 64having a perimeter and a peripheral wall 66 joining the main wall 64 atthe perimeter. The peripheral wall 66 may be generally perpendicular tothe main wall 64, but preferably flares slightly outwardly fromperpendicular to define a cavity 68 for receiving the first mountingportion 24. The drape 62 is attached to the peripheral wall 66 of theinterface 60 (See FIG. 8). The drape 62 is absent in FIGS. 2-4, 9, and16 to better illustrate other components.

The main wall 64 has a plurality of separated support sections 70, 72,74, 76 having a larger thickness. The main wall 64 has a width of fromabout 0.050 to about 0.150 inches between the support sections 70, 72,74, 76 and a width of from about 0.150 to about 0.250 inches at thesupport sections 70, 72, 74, 76. The main wall 64 has a Durometer ofShore A 80.

The interface 60 includes the balls 28 integrated therein. In oneembodiment, the balls 28 are insert molded in three of the supportsections 70, 72, 74. As described above, the balls 28 are arranged forreceipt in the first and second plurality of receptacles 30, 32, 34, 36,38, 40 to kinematically couple the first and second mounting portions24, 26. The balls 28 are located so that the barrier remains unbrokenbetween the support sections 70, 72, 74 and the balls 28 to reduce thepotential for migration of contaminants through the interface 60. Thus,the drape 62 and the interface 60 provide a continuous barrier to themigration of contaminants from the robotic arm R into the sterile fieldS.

In one embodiment, the balls 28 have polished, corrosion-resistantsurfaces, so that under certain loads submicron repeatability inpositioning the mounting portions 24, 26 can be achieved. The balls 28may be formed of ceramic, stainless steel, or other suitable materials.The balls 28 may be formed of silicon carbide or tungsten carbide. Theballs 28 may be precision machined to very tight tolerances, for exampleless than fifty millionths of an inch.

The interface 60 includes a plurality of electrical terminals. In theembodiment shown, the electrical terminals are pins 78 that may beinsert molded into the main wall 64. The pins 78 are located so that thebarrier remains unbroken between the main wall 64 and the pins 78 toreduce the potential for contaminants to migrate through the interface60. The pins 78 transfer electrical power/signals across the sterilebarrier assembly 22.

The interface 60 includes a preloading element. In the embodiment shown,the preloading element is an elongated load bar 80. The load bar 80 maybe insert molded into one of the support sections. The load bar 80 isformed with rounded indentations on sides thereof to facilitateembedding in the support section so that the load bar 80 remains fixedto the interface 60 during use. The load bar 80 is located such that thebarrier remains unbroken between the support section and the load bar 80to reduce the potential for migration of contaminants through theinterface 60. Thus, the drape 62 and interface 60 provide a continuousbarrier to the migration of contaminants from the robotic arm R into thesterile field S.

The load bar 80 has first and second ends. The load bar 80 may be formedof stainless steel, Kevlar composite, or other suitably rigid materials.The load bar 80 defines apertures 82 near each of the ends. Inserts 84are located in the apertures 82. The inserts 84 are in the form ofcylindrical bushings. The inserts 84 are formed of stainless steel orsilicone nitride. In some embodiments, the load bar 80 is employedwithout inserts.

Referring to FIGS. 9-11, a preloading mechanism 86 clamps the mountingportions 24, 26 in position once they are brought together inapproximate final orientation. In the embodiment shown, the load bar 80forms part of the preloading mechanism 86 and also acts as an initialsupport member to hold the protective covering 58 on the robotic arm R.A preload force is applied to the load bar 80. The preload force issized to exceed anticipated loading through the kinematic coupling sothat the kinematic coupling and associated properties are maintained.

The preloading mechanism 86 further includes a first catch 88. The firstcatch 88 is slidably disposed in a catch guide 90 to move from anunlatched position to a latched position. The catch guide 90 is held ina first inner cavity 92 (see FIG. 4) defined in the first body 42. Thecatch guide 90 defines an oblong through passage 94 in which the firstcatch 88 slides.

As shown in FIG. 11, a first spring 96 biases the first catch 88laterally from a side wall 98 of the first body 42 into the latchedposition. A first release button (not shown) can be slidably disposed inthe first body 42 to release the first catch 88. The first releasebutton may simply be depressed to slide the first catch 88 from thelatched position to the unlatched position.

A load bar receiver 100 defines another oblong passage 102. The oblongpassages 94, 102 of the catch guide 90 and the receiver 100 align withone another so that the first catch 88 is slidable therein to move fromthe unlatched position to the latched position. The receiver 100 iscylindrical. The receiver 100 further defines a load bar slot 104therethrough. The load bar slot 104 is arranged perpendicularly to theoblong passage 102 in the receiver 100 to receive the first end of theload bar 80.

During use, the first end of the load bar 80 is inserted into the loadbar slot 104 until one of the apertures 82 in the load bar 80 is engagedby the first catch 88 (see FIGS. 4 and 9). Once the load bar 80 is fullyengaged by the first catch 88, the sterile barrier assembly 22 isgenerally supported on the first mounting portion 24 for furthermanipulation. Thus, the load bar 80 and the first catch 88 function asan initial support mechanism for the sterile barrier assembly 22.

Referring to FIGS. 9 and 12-15, the preloading mechanism 86 furtherincludes a second catch 106. The second catch 106 is slidably disposedin the second body 46. More specifically, the second mounting portion 26defines a second inner cavity 108 in which the second catch 106 isslidable between unlatched and latched positions.

A second spring 110 biases the second catch 106 laterally from a sidewall 112 of the second body 46 into the latched position. A secondrelease button 114, like the first, can be slidably disposed in thesecond body 46 to release the second catch 106. The second releasebutton 114 may simply be depressed to slide the second catch 106 fromthe latched position to the unlatched position.

The second cover plate 48 fixed to the second body 46 has an elongatedslot 116 (see FIG. 6) sized to receive the second end of the load bar 80opposite the first end inserted into the receiver 100.

During use, the second end of the load bar 80 is inserted into theelongated slot 116 until the other aperture 82 in the load bar 80 isengaged by the second catch 106. Once the load bar 80 is fully engagedby the second catch 106, the sterile barrier assembly 22 and the secondmounting portion 26 are generally supported on the first mountingportion 24 for further installation. Thus, the load bar 80, the firstcatch 88, and the second catch 106 also function as a support mechanismfor the sterile barrier assembly 22 and the second mounting portion 26.

As shown in FIG. 9, the preloading mechanism further includes atensioner 118 operatively coupled to the load bar 80. The tensioner 118applies tension to the load bar 80 and clamps the first and secondmounting portions 24, 26 together with the preload force such that theballs 28 seat into the first and second plurality of receptacles 30, 32,34, 36, 38, 40.

Referring to FIGS. 12 and 13, the tensioner 118 applies tension to theload bar 80 by moving the second catch 106 with respect to the firstcatch 88. The second catch 106, while slidable in the second body 46between unlatched and latched positions, is also pivotally supported inthe second body 46 about a pivot shaft 120. The pivot shaft 120 islocated in a pair of support bores 122, 124 in the second body 46. Thesecond catch 106 defines a pivot bore 126 (see FIG. 14) therethrough forreceiving the pivot shaft 120. As a result, the second catch 106 is ableto pivot about the pivot shaft 120.

The tensioner 118 includes a cam shaft 128. The cam shaft 128 isrotatable between tensioned and untensioned positions. The cam shaft 128is rotatably supported in a pair of support bores 130, 132 in the secondbody 46. The cam shaft 128 has first and second cylindrical shaftsections 134, 136 that are rotatably supported in the support bores 130,132 by bushings 138.

The cam shaft 128 includes a cam section 140 (see FIGS. 9 and 15)between the first and second shaft sections 134, 136. The cam section140 is offset from the first and second shaft sections 134, 136. The camsection 140 is disposed in a cam passage 142 defined in the second catch106 (see FIG. 14). The cam passage 142 is rectangular in shape andextends through the second catch 106 near one end of the second catch106, while the pivot bore 126 extends through the second catch 106 nearan opposite end. When the cam shaft 128 begins rotation toward thetensioned position, the cam section 140 contacts an inner surface 144defining the cam passage 142. Further rotation of the cam shaft 128causes additional camming action by the cam section 140 against theinner surface 144 which pivots the second catch 106 about the pivotshaft 120 so that tension is placed on the load bar 80.

The tensioner 118 also includes a lever 146 rotatably fixed to the camshaft 128 via a lever attachment 148. The lever attachment 148 has ageometric shape that conforms to a shape of a cavity (not shown) in thelever 146 so that actuation of the lever 146 results in rotation of thecam shaft 128. The cam shaft 128 is rotated at least ninety degrees tomove between the untensioned and tensioned positions. Of course, otherpositions therebetween may place tension on the load bar 80 and could besuitable for applying the desired preload force.

The lever 146 is locked when the cam shaft 128 is placed in the desiredposition, e.g., the tensioned position. In the tensioned position, thepreload tensile force is applied to the load bar 80. By locking thelever 146 after applying the preload force, the preload force iscontinually applied during use of the robotic arm R and end effector EEto maintain the kinematic coupling. The preloading mechanism 86transfers the preload force across the sterile barrier assembly 22without piercing the barrier.

When the tensioner 118 applies the preload force to the load bar 80, adisc spring 150 applies a compressive force equal to the preload forceto the load bar 80. The disc spring 150 is contained between two springshims 152. The disc spring 150 biases the catch guide 90, receiver 100,and first catch 88 toward a rear wall 154 of the first body 42. The discspring 150 biases the load bar 80 by virtue of the load bar 80 beinglatched to the first catch 88.

As the balls 28 are aligned within the first and second plurality ofreceptacles 30, 32, 34, 36, 38, 40, and the preload force is applied,some stretching and/or flexing of the interface 60 is possible betweenthe balls 28 so that the balls 28 properly seat in the receptacles 30,32, 34, 36, 38, 40, particularly when the second plurality ofreceptacles 36, 38, 40 have conical configurations (which engage each ofthe balls 28 at three contact points). This stretching and/or flexingoccurs without breaking the barrier. Thus, the balls 28 are able to moveinto the receptacles 30, 32, 34, 36, 38, 40 upon preloading. Theseproperties of the interface 60 account for manufacturing tolerances. Inother words, the interface 60 is able to stretch and/or flex withoutbreaking contact or a seal with the balls 28, such as the contact orseal created during molding.

Once seated, positions of the balls 28 are fixed relative to the firstand second plurality of receptacles 30, 32, 34, 36, 38, 40. As a result,the first and second mounting portions 24, 26 are kinematically coupledtogether without piercing the sterile barrier assembly 22. The kinematiccoupling allows the end effector EE to be readily released from andrejoined to the robotic arm R at the same location. The kinematiccoupling also allows the end effector EE to be readily released from therobotic arm R so that different end effectors with similar mountingportions can be kinematically coupled to the robotic arm R.

FIG. 16 shows electrical power and/or other signal connections that canbe made through the sterile barrier assembly 22. These connectionsemploy the pins 78. These pins 78 electrically interconnect electricalconnectors attached to the first and second mounting portions 24, 26.

In the embodiment shown in FIGS. 5, 6, and 16, the first mountingportion 24 includes a first electrical connector base 156. The firstelectrical connector base 156 is fixed in a communication cavity 158defined in the first body 42. The first cover plate 44 defines anopening 160 into the communication cavity 158. A wireway 162 is alsodefined in the first body 42 to carry wires away from the firstelectrical connector base 156. A plurality of pogo pin connectors 164,e.g., spring-loaded electrical connectors, are movably supported by thefirst electrical connector base 156.

The second mounting portion 26 includes a second electrical connectorbase 166. The second electrical connector base 166 is fixed in anopening 168 in the second cover plate 48. A plurality of electricalreceiver terminals 170 are supported by the second electrical connectorbase 166. When the first and second mounting portions 24, 26 arekinematically coupled together and preloaded, the electrical receiverterminals 170 receive the pins 78 of the interface 60. Likewise, thepogo pin connectors 164 make contact with the pins 78 of the interface60 so that power or other electrical signals can flow through the pins78. Thus, power, communication signals, or other signals can be passedfrom the robotic arm R to the end effector EE and vice versa.

Referring to FIGS. 17-32, an alternative mounting system 220 is shownfor kinematically coupling the first and second surgical components(e.g., robotic arm R and end effector EE) using a sterile barrierassembly 222.

In this embodiment, the robotic arm R includes a first mounting portion224 and the end effector EE includes a second mounting portion 226. Thesterile barrier assembly 222 is located between the first and secondmounting portions 224, 226 to establish the barrier between the roboticarm R and the end effector EE during surgery.

Referring to FIGS. 18 and 19, a plurality of kinematic couplers are usedto kinematically couple the first and second mounting portions 224, 226.In this embodiment, the kinematic couplers are spherical balls 228. Theballs 228 are seated in first and second pluralities of receptacles 230,232, 234, 236, 238, 240. The receptacles 230, 232, 234, 236, 238, 240are sized and shaped to receive the balls 228. The first mountingportion 224 includes a first body 242 and a first cover plate 248 fixedto the first body 242. The first plurality of receptacles 230, 232, 234are fixed in the first body 242. The second mounting portion 226includes a second body 246. The second plurality of receptacles 236,238, 240 are fixed in the second body 246.

Referring to FIG. 20, the first plurality of receptacles 230, 232, 234includes one receptacle 230 having a contact surface 250 with a conicalconfiguration (also referred to as a cone receptacle). Anotherreceptacle 232 has a pair of contact surfaces 252 provided by a V-shapedgroove (also referred to as a V-grooved receptacle). Yet anotherreceptacle 234 has a contact surface 254 including a flat (also referredto as a planar receptacle). The contact surfaces 252 of the V-groovedreceptacle or the contact surface 254 of the planar receptacle may begenerally flat or may be concave with the surfaces 252, 254 having aconcavity that results in only a single point of contact with the balls228. In some versions, the contact surfaces 252 of the V-groovedreceptacle are in the shape of a gothic arch.

The second plurality of receptacles 236, 238, 240 includes threereceptacles having contact surfaces 256 with conical configurations(i.e., cone receptacles). Three balls 228 are captured betweencorresponding, aligned pairs of the receptacles, i.e, receptacle 230 toreceptacle 236, receptacle 232 to receptacle 238, and receptacle 234 toreceptacle 240, as shown in FIGS. 20 and 21.

The receptacles 230, 232, 234, 236, 238, 240 may be formed of steel orother suitably rigid materials and may be separate components rigidlyconnected to the bodies 242, 246 or may be integral with the bodies 242,246. The receptacles 230, 232, 234, 236, 238, 240 may be integrated intothe mounting portions 224, 226 or otherwise attached to the mountingportions 224, 226 in numerous ways.

When the mounting portions 224, 226 are brought together in approximatefinal orientation with the sterile barrier assembly 222 positionedtherebetween, the balls 228 of the sterile barrier assembly 222self-seat into the receptacles 230, 232, 234, 236, 238, 240. The conereceptacle, V-grooved receptacle, and planar receptacle of the firstmounting portion 224 remove, three, two, and one degrees of freedom,respectively. Thus, exactly six degrees of freedom are constrained. Inother embodiments, described further below, each of the first pluralityof receptacles 230, 232, 234 of the first mounting portion 224 mayremove two degrees of freedom via two points of contact with the balls228. In either of these cases, exactly six degrees of freedom areconstrained via exactly six contact points, e.g., one contact point foreach degree of freedom.

Referring to FIGS. 22-26, the sterile barrier assembly 222 includes aprotective covering 258. The protective covering 258 includes aninterface 260 and a drape 262 attached to the interface 260. The drape262 has an interior surface and an exterior surface. The interiorsurface is placed adjacent to the robotic arm R during surgery. In thisembodiment, the drape 262 is fitted to the robotic arm R to generallyencompass the robotic arm R. The drape 262 is formed of at least one ofpolyethylene, polyurethane, and polycarbonate. The drape 262 may beattached to the interface 260 by ultrasonic welding, tape, adhesive, orthe like. The drape 262 is attached to the interface 260 so that noperforations are present or are sealed, i.e., the drape forms acontinuous barrier with the interface 260. The drape 62 is absent inFIGS. 17-19 and 24-27 to better illustrate other components.

Referring to FIGS. 25 and 26, in the embodiment shown, the interface 260includes a latch bracket 263 formed of a rigid material such as aluminumor stainless steel. The latch bracket 263 includes a main wall 264 (seeFIG. 26) having a perimeter and an inner wall 266 extending from themain wall 264. The inner wall 266 may be generally perpendicular to themain wall 264. The latch bracket 263 includes a pair of latches 265 (seealso FIG. 23) extending from the main wall 264 in a direction oppositethe inner wall 266. The latches 265 may be in the form of latch hooks.The latches 265 interact with and engage a first catch 288 of the firstmounting portion 224 as described below.

The interface 260 further includes a cover 269 having a peripheral lip271. The cover 269 may be formed of injection molded plastic. Theperipheral lip 271 snap-fits over the main wall 264 so that the cover269 is secured to the latch bracket 263. When secured, the cover 269includes an outer wall 273 surrounding the inner wall 266 of the latchbracket 263. The cover 269 also includes a wall 275. The wall 275extends from a base of the outer wall 273 to the peripheral lip 271. Inaddition to the snap-fit connection, the cover 269 may be fixed to thelatch bracket 263 by adhesive between the wall 275 and the main wall 264of the latch bracket 263. A seal (not shown) may be located between anedge of the main wall 264 and an inner edge of the peripheral lip 271 tofurther enhance the barrier.

The peripheral lip 271 defines an attachment groove 277 in which thedrape 262 is attached to the interface 260. The attachment groove 277may receive, for example, an elastic band of the drape 262, tape for thedrape 262, a snap-ring of the drape 262, and the like.

The interface 260 includes the balls 228 integrated therein. In thisembodiment, the balls 228 are located in ball openings defined in themain wall 264 of the latch bracket 263. The ball openings are sized sothat a portion of each of the balls 228 protrudes on either side of themain wall 264. The main wall 264 includes a stop 279 in each of the ballopenings. In the embodiment shown, the stop 279 is a radially inwardlydirected tapered surface of the main wall 264. The tapered surfacedefines an opening having a diameter slightly smaller than a diameter ofthe balls 228 to prevent the balls 228 from passing entirely through themain wall 264 (see FIG. 18).

During assembly the balls 228 are dropped into the ball openings in themain wall 264. The stop 279 prevents the balls 228 from passing entirelythrough the ball openings while still allowing a portion of the balls228 to protrude beyond the main wall 264. The cover 269 is then snap-fitover the latch bracket 263 to hold the balls 228 in place in the ballopenings. The wall 275 of the cover 269 defines a plurality of secondaryball openings 267 that are in line with the ball openings in the mainwall 264 yet sized slightly smaller than a diameter of the balls 228. Asa result, the balls 228 are able to protrude beyond the wall 275 yet beheld in placed between the wall 275 and the main wall 264.

The main wall 264 has a plurality of counterbores 284 that furtherdefine the ball openings. The counterbores 284 are sized with a diameterslightly larger than each of the balls 228 so that the balls 228 can beseated in the ball openings. The counterbores 284 are also sized so thatseals 281 such as o-rings can be placed in the counterbores 284 to sealabout the balls 228 and against the main wall 264. As shown, two seals281 are located in each of the counterbores 284 (see also FIG. 18). Theseals 281 are held in place by virtue of the wall 275 being located overthe seals 281. The wall 275 engages one of each pair of seals 281 tofurther enhance the barrier.

The seals 281 are resilient so that the balls 228 are able to moveslightly laterally in the ball openings, e.g., the balls 228 are notconstrained from lateral movement in the ball openings. As a result,distances between the balls 228 are able to adjust, e.g., increase ordecrease, so that the balls 228 seat properly into the receptacles 230,232, 234, 236, 238, 240, particularly when each of the second pluralityof receptacles 236, 238, 240 have conical configurations, which arerigidly fixed in position relative to one another. Owing to the abilityof the balls 228 to adjust laterally, the balls 228 are able to fitneatly into the conical receptacles, thereby enabling three points ofcontact with the balls 228.

As described above, the balls 228 are arranged for receipt in the firstand second plurality of receptacles 230, 232, 234, 236, 238, 240 tokinematically couple the first and second mounting portions 224, 226.The balls 228 are located so that the barrier remains unbroken betweenthe main wall 264 and the balls 228 to reduce the potential formigration of contaminants through the interface 260. Thus, the drape 262and interface 260 provide a continuous barrier to the migration ofcontaminants from the robotic arm R into the sterile field S.

In this embodiment, the balls 228 have polished, corrosion-resistantsurfaces, so that under certain loads submicron repeatability inpositioning the mounting portions 224, 226 can be achieved. The balls228 may be formed of ceramic, stainless steel, or other suitablematerials. The balls 228 may be formed of silicon carbide or tungstencarbide. The balls 228 may be precision machined to very tighttolerances, for example less than fifty millionths of an inch.

The interface 260 includes a plurality of electrical terminals embeddedin the cover 269, as shown in FIG. 24. In this embodiment, theelectrical terminals are pins 278 that may be insert molded into thecover 269 of the interface 260. The pins 278 are located in a connectorportion 274 of the cover 269. The connector portion 274 partially passesthrough an aperture 276 in the latch bracket 263. The connector portion274 may be press fit into the aperture 276 to reduce the potential forcontaminants to migrate through the interface 260. A peripheral seal(not shown) may also be present to seal against the connector portion274 and the main wall 264 in the aperture 276 to further reduce thepotential for contaminants to migrate through the interface 260. Thepins 278 transfer electrical power/signals across the sterile barrierassembly 222.

Referring to FIGS. 18-20, the first mounting portion 224 includes afirst catch 288. In this embodiment, the first catch 288 is a slidingcatch plate. The first catch 288 defines a pair of spaced apertures 289(FIG. 20). The first catch 288 is slidably disposed in the first body242. The first body 242 includes a forward wall 285. A cover plate 293is mounted to the forward wall 285 to define a catch guide recess 287.The first catch 288 slides in the catch guide recess 287.

One or more compression springs 291 biases the first catch 288 upwardlyso that an upper edge of the first catch 288 contacts a downwardlyfacing edge of the forward wall 285 defining the catch guide recess 287.The compression springs 291 act between a lower edge of the first catch288 and an opposing upwardly facing edge of the forward wall 285defining the catch guide recess 287.

The forward wall 285 also defines a latch aperture 295 through which thelatches 265 are able to engage the first catch 288. In the normal state,the apertures 289 are only partially aligned with the latch aperture295, as shown in FIG. 20. Still, a large enough portion of the apertures289 are exposed through the latch aperture 295 for the latches 265 toengage the first catch 288.

Each of the latches 265 has a head 297 that tapers to a front surfacesized to fit within the exposed portion of the apertures 289. As thefront surfaces of each head 297 moves into and through the exposedportion of the apertures 289, a tapered surface of the head 297 cams thefirst catch 288 downwardly against the bias of the compression springs291 until the head 297 moves entirely through the apertures 289. Oncethe heads 297 have passed entirely through the apertures 289, the firstcatch 288 slides upwardly into a latch recess 299 defined by each of theheads 297 under the bias of the compression springs 291. This holds thelatch bracket 263, and by extension the entire sterile barrier assembly222, onto the first body 242.

This latch/catch arrangement allows the interface 260 to engage thefirst body 242 without requiring any tilting therebetween. In otherwords, the interface 260 can be pressed into engagement with the firstbody 242 by solely translational or linear movement of the interface260. This further facilitates the engagement of the pins 278 intocorresponding electrical connectors 251, 257 on the first body 242 andsecond body 246. It should be appreciated that the latches 265 and thefirst catch 288 could be reversed or that the latches 265 and the firstcatch 288 could be referred to as catches 265 and the first latch 288.

An actuator 301 is used to release the latch bracket 263 from the firstbody. The actuator 301 is fixed to the first catch 288. In thisembodiment, the actuator 301 is U-shaped and can be actuated by pressingthe actuator 301 downwardly to move the first catch 288 downwardlyagainst the bias of the compression springs 291 so that the heads 297 ofthe latches 265 can be pulled back out through the apertures 289 and thelatch aperture 295.

Referring to FIG. 19, with the interface 260 supported by the first body242, the second body 246 is ready to engage the interface 260. A latchhook 283 is located to easily engage a second catch 306 fixed to thesecond body 246 (or could be referred to as the catch hook 283 and thesecond latch 306). The latch hook 283 is pivotally supported by thelatch bracket 263. A torsion spring (not numbered in FIG. 26) biases thelatch hook 283 into engagement with the second catch 306.

The second catch 306 is a D-shaped rod fixed to the second body 246 andshaped to engage the latch hook 283. The second body 246 is simplypressed onto the interface 260 until the latch hook 283 engages thesecond catch 306. More specifically, as the second body 246 is pressedonto the interface 260, the second catch 306 presses against a taperedface of of the latch hook 283 thereby urging the latch hook 283 to pivotupwardly against the bias of the torsion spring until a recess in thelatch hook 283 aligns with the second catch 306 at which time thetorsion spring urges the latch hook 283 over the second catch 306, asshown in FIG. 19. Now the mounting system 220 is ready to be preloadedand prepared for use. In this state, the mounting system 220 acts as asupport mechanism to support the end effector EE on the robotic arm Rprior to preloading.

Referring to FIGS. 25-27, a preloading mechanism 286 clamps the mountingportions 224, 226 together in position once they are brought together inapproximate final orientation. A preloading element is located in theinterface 260. In this embodiment, the preloading element is anelongated load member 280. The load member 280 is movably supported inthe interface 260. The load member 280 has first and second ends. Theload member 280 may be formed of stainless steel, Kevlar composite, orother suitably rigid materials. The load member 280 defines an aperture282 near one end and the latch hook 283 adjacent the opposite end.

A preload force is applied to the load member 280. The preload force issized to exceed anticipated loading through the kinematic coupling sothat the kinematic coupling and associated properties are maintained.

The load member 280 is movably supported by the latch bracket 263. Inparticular, the load member 280 is able to move from an unloadedposition to a loaded position relative to the latch bracket 263. In theunloaded position, the latch hook 283 is located to engage the secondcatch 306. In the loaded position, the load member 280 is urged towardthe latch bracket 263 to load the mounting system 220.

The preloading mechanism 286 further includes a tensioner 318 (FIG. 26)and a spring cup 305 coupled to the tensioner 318. The tensioner 318includes a cam shaft 328 that fits inside a pair of concentric inner andouter tubes 307, 309. The tubes 307, 309 are hollow and cylindrical. Thetubes 307, 309 are fixed from translation relative to the spring cup 305so that as the tubes 307, 309 move in translation, so does the springcup 305.

The spring cup 305 defines a first cup opening 311 (FIG. 25) that issized to receive the outer tube 309. Opposite the first cup opening 311,the spring cup 305 defines a spring cup counterbore 315 (FIG. 25) sizedto receive the outer tube 309. The outer tube 309 may be press fit intothe first cup opening 311 and the spring cup counterbore 315 so that theouter tube 309 is unable to rotate relative to the spring cup 305, orthe outer tube 309 may be allowed to rotate therein but be fixed frommoving in translation relative to the spring cup 305. The outer tube 309passes through the aperture 282 of the load member 280.

The latch hook 283 protrudes beyond a central opening in the spring cup305. The latch hook 283 also protrudes beyond a central opening in a topof the outer wall 273 to reach the second catch 306 of the second body246. The spring cup 305 is sized so that the spring cup 305 is unable topass through the central opening in the top of the outer wall 273. Thespring cup 305 and outer wall 273 have chamfered surfaces configured toclear one another in the unloaded state when the latch hook 283 isreleased as described further below.

The cam shaft 328 is supported for rotation by the inner wall 266 of thelatch bracket 263. The inner wall 266 defines a pair of throughbores 301(FIG. 26). A pair of bushings 338 are press fit into the throughbores301 and rotatably support outer cylindrical sections 334 of the camshaft 328. As a result, the cam shaft 328 is able to rotate relative tothe latch bracket 263 between tensioned and untensioned positions. Thecam shaft 328 includes a pair of cam sections 340 separated by a middlecylindrical section 336. The cam sections 340 have an outer diameterslightly smaller than an inner diameter of the inner tube 307. Thecylindrical sections 336 of the cam shaft 328 have a smaller diameterthan the cam sections 340 thereby creating a camming action as the camshaft 328 is rotated.

The inner and outer tubes 307, 309 each have a length less than a lengthacross opposing sections of the inner wall 266 between the throughbores301. As a result, the inner and outer tubes 307, 309 can move intranslation relative to the inner wall 266. As the cam shaft 328 isrotated, the inner and outer tubes 307, 309 move under the cam action ofthe cam shaft 328 toward and away from the main wall 264. This movementprovides the preloading needed to load the load member 280 once thelatch hook 283 has engaged the second catch 306.

The tensioner 318 also includes a lever 346 rotatably fixed to the camshaft 328. The lever 346 includes a boss 348 having a D-shaped bore toreceive the D-shaped portion of the cam shaft 328 so that the cam shaft328 rotates as the lever 346 rotates. A fastener (not numbered) engagesa threaded end of the cam shaft 328 to secure the lever 346 to the camshaft 328. The cam shaft 328 is rotated at least ninety degrees to movebetween the unloaded and loaded positions. Of course, other positionstherebetween may place tension on the load member 280 and could besuitable for applying the desired preload force.

The lever 346 may be locked when the cam shaft 328 is placed in thedesired position, e.g., the loaded position. In the loaded position, thepreload tensile force is applied to the load member 280. By locking thelever 346 after applying the preload force, the preload force iscontinually applied during use of the robotic arm R and end effector EEto maintain the kinematic coupling. The preloading mechanism 286transfers the preload force across the sterile barrier assembly 222without piercing the barrier.

The tensioner 318 applies the preload force to the load member 280through a conical disc spring 350, such as a Belleville spring. The discspring 350 applies a force equal to the preload force to the load member280. The disc spring 350 acts between the spring cup 305 and a shoulder317 of the load member 280. In particular, as the lever 346 is rotated,the cam shaft 328 rotates and the cam sections 340 move the inner andouter tubes 307, 309, and by extension the spring cup 305, away from thelatch hook 283 (now engaging the second catch 306). The inner and outertubes 307, 309 are also able to move relative to the load member 280 byvirtue of moving in the aperture 282, which is elongated to accommodatefor such movement. The movement of the spring cup 305 relative to theload member 280 compresses the disc spring 350 and applies the preloadforce onto the load member 280 via the shoulder 317.

Since the balls 228 are aligned with the first and second plurality ofreceptacles 230, 232, 234, 236, 238, 240, once the preload force isapplied, the balls 228 become seated in the receptacles 230, 232, 234,236, 238, 240. Once seated, positions of the balls 228 are fixed and thepositions of the first and second plurality of receptacles 230, 232,234, 236, 238, 240 are fixed relative to one another. As a result, thefirst and second mounting portions 224, 226 are kinematically coupledtogether without piercing the sterile barrier assembly 222.

Release of the latch hook 283 is facilitated by urging the latch hook283 upwardly away from the second catch 306. This is accomplished byrotating the lever 346 further counterclockwise when in the unloadedposition. This movement causes the cam shaft 328 to interact with asecond cup opening 313 defined in the spring cup 305 to pivot the springcup 305 and the latch hook 283 to release the latch hook 283 from thesecond catch 306.

The second cup opening 313 is smaller than the outer tube 309, yet largeenough to accommodate an eccentric portion 325 of the cam shaft 328. Thesecond cup opening 313 has an eccentric shape as shown in FIG. 26A andis dimensioned so that in the unloaded position the eccentric portion325 rests in the location indicated in solid lines in FIG. 26A. Fromthis position, when the eccentric portion 325 is further rotatedcounterclockwise via lever 346, the eccentric portion 325 engages thespring cup 305 in a manner that causes pivoting of the spring cup 305.More specifically, since the eccentric portion 325 is constrained fromfurther rotating counterclockwise given the dimensions of the second cupopening 313 (as viewed in FIG. 26A), further counterclockwise motion ofthe lever 346 pivots the spring cup 305 relative to the outer wall 273,and thereby moves the latch hook 283 upwardly away from the second catch306. In the loaded position, the eccentric portion 325 rests in thelocation indicated by dashed lines in FIG. 26A.

FIG. 19 shows electrical power and/or other signal connections that canbe made through the sterile barrier assembly 222. These connectionsemploy the pins 278 embedded in the interface 260. These pins 278electrically interconnect electrical connectors 251, 257 attached to thefirst and second mounting portions 224, 226.

In this embodiment, the first mounting portion 224 includes the firstelectrical connector 251. The first electrical connector 251 is able tofloat relative to the first body 242. The second mounting portion 226includes the second electrical connector 257. The second electricalconnector 257 also floats relative to the second body 246. When thefirst and second mounting portions 224, 226 are kinematically coupledtogether and preloaded, the electrical connectors 251, 257 receive thepins 278 so that power or other electrical signals can flow through thepins 278. Thus, power, communication signals, or other signals can bepassed from the robotic arm R to the end effector EE and vice versa.

FIG. 32 shows the steps of attaching the sterile barrier assembly 222first to the first mounting portion 224 (which is fixed to the roboticarm R), then attaching the second mounting portion 226 (shown in phantomintegrated into the end effector EE) to the sterile barrier assembly222, and then pivoting the lever 346 downwardly to load the mountingsystem 220 and apply the preload force necessary to maintain positioningbetween the first mounting portion 224 and the second mounting portion226.

Referring to FIGS. 33-47, another alternative mounting system is shownfor kinematically coupling the first and second surgical components(e.g., robotic arm R and end effector EE) using a sterile barrierassembly 422.

Referring to FIGS. 33-36, a plurality of kinematic couplers, similar tothose of prior embodiments, are used to kinematically couple the endeffector EE to the robot arm R. In this embodiment, the kinematiccouplers are spherical balls 428. The balls 428 are seated in first andsecond pluralities of receptacles 432, 438 (one pair shown in FIG. 36).The receptacles 432, 438 are sized and shaped to receive the balls 428,as previously described. The first plurality of receptacles 432 arefixed to a first mounting portion 424 of the robot arm R and the secondplurality of receptacles 438 are fixed to a second mounting portion 426of the end effector EE.

The first plurality of receptacles 432 includes three receptacles (onlyone shown in FIG. 36). Each of the first plurality of receptacles 432has a pair of contact surfaces 452 provided by a V-shaped groove orgothic arch (also referred to as V-grooved receptacles). The secondplurality of receptacles 438 includes three receptacles (only one shownin FIG. 36). Each of the second plurality of receptacles has a contactsurface 456 with a conical configuration (i.e., cone receptacles). Threeballs 428 are captured between corresponding, aligned pairs of thereceptacles 432, 438.

When the mounting portions 424, 426 of the robot arm R and the endeffector EE are brought together in approximate final orientation withthe sterile barrier assembly 422 positioned therebetween, the balls 428of the sterile barrier assembly 422 self-seat into the receptacles 432,438 so that exactly six degrees of freedom are constrained, as describedin the prior embodiments.

The sterile barrier assembly 422 includes a protective covering 458. Theprotective covering 458 includes an interface 460 and a drape 462attached to the interface 460. The drape 462 has an interior surface andan exterior surface. The interior surface is placed adjacent to therobotic arm R during surgery. The drape 462 is formed of at least one ofpolyethylene, polyurethane, polycarbonate, or other suitable materials.The drape 462 may be directly attached to the interface 460 byultrasonic welding, tape, adhesive, or the like.

In the embodiment shown, the drape 462 comprises a ring 468 that engagesthe interface 460. The ring 468 defines an opening. In the embodimentshown, the ring 468 is a snap-ring. A flaccid portion of the drape 462is attached to the snap-ring 468 to surround the opening by ultrasonicwelding, tape, adhesive, or the like. When draping the robot arm R, thesnap-ring 468 (with flaccid portion attached thereto) is first snap-fitto the interface 460, prior to the interface 460 being mounted to thefirst mounting portion 424 of the robot arm R. The interface 460 fitsinto the opening in the snap-ring 468. Once the snap-ring 468 issnap-fit to the interface 460, the interface 460 is mounted to the firstmounting portion 424 of the robot arm R. The drape 462 is attached tothe interface 460 so that no perforations are present or are sealed,i.e., the drape 462 forms a continuous barrier with the interface 460through the snap-ring 468 or other similar attachment mechanism. Thedrape 462 is absent in several Figures to better illustrate othercomponents.

Referring to FIGS. 36 and 37, in the embodiment shown, the interface 460comprises a back plate assembly 459 that is secured to a cover 469. Theback plate assembly 459 is formed of two separate components—a back ringplate 461 that is mounted by fasteners to the cover 469 and a back coverplate 467 that is captured between the back ring plate 461 and the cover469.

Referring to FIGS. 38 and 39, the interface 460 further includes a latchassembly 463. The latch assembly 463 includes a latch bracket 464 havingspaced apart inner walls 466. A pair of latches 465 are held within atravel passage defined in the latch bracket 464 by the spaced apartinner walls 466.

The back cover plate 467 is fixed to the latch bracket 464 (e.g., viafasteners) and spaced from the latch bracket 464 to further define thetravel passage for the latches 465. Each of the latches 465 are capturedin the travel passage. A pair of biasing members B, such as springs,bias the latches 465 toward each other. The biasing members B actbetween the inner walls 466 and the latches 465. In this embodiment, thelatches 465 are in the form of latch plates with arcuate recesses (seeFIG. 46) to engage a first catch 488 of the first mounting portion 424as described below.

The cover 469 has a peripheral lip 471. The cover 469 may be formed ofinjection molded plastic or metal. The peripheral lip 471 is securedaround the back plate assembly 459. The cover 469 includes an outer wall473 and a wall 475. The wall 475 extends from a base of the outer wall473 to the peripheral lip 471. Seals (not shown) may be located betweenthe cover 469 and the back plate assembly 459 to further enhance thebarrier.

The interface 460 includes the balls 428 integrated therein. In thisembodiment, the balls 428 are located in ball openings defined in thecover 469 and the back ring plate 461. The ball openings are sized sothat a portion of each of the balls 428 protrudes out from the back ringplate 461 and the wall 475 of the cover 469 to engage the receptacles432, 438. Seals that are X-shaped in cross-section hold the balls 428 inthe ball openings and provide a sterile barrier around the balls 428,while still allowing the balls 428 lateral movement within the ballopenings.

As described above, the balls 428 are arranged for receipt in thereceptacles 432, 438 to kinematically couple the mounting portions 424,426. The balls 428 are located so that the barrier remains unbrokenbetween the back ring plate 461 and the balls 428 to reduce thepotential for migration of contaminants through the interface 460. Thus,the drape 462 and interface 460 provide a continuous barrier to themigration of contaminants from the robotic arm R into the sterile fieldS.

In this embodiment, the balls 428 have polished, corrosion-resistantsurfaces, so that under certain loads submicron repeatability inpositioning the mounting portions 424, 426 can be achieved. The balls428 may be formed of ceramic, stainless steel, or other suitablematerials. The balls 428 may be formed of silicon carbide or tungstencarbide. The balls 428 may be precision machined to very tighttolerances, for example less than fifty millionths of an inch.

The first mounting portion 424 includes the first catch 488. In thisembodiment, the first catch 488 is a catch post having a head 497 and agroove 498 proximal to the head 497. The latches 465 engage the firstcatch 488 in the groove 498. The back cover plate 467 defines a latchaperture 495 through which the head 497 is able to engage the latches465. The head 497 is tapered to engage the latches 465. Morespecifically, the head 497 is tapered to spread apart the latches 465from their normal positions (see FIG. 38). As the head 497 moves betweenthe latches 465, a tapered surface of the head 497 spreads the latches465 apart against the bias of the biasing members B until the head 497moves entirely past the latches 465. Once the head 497 is past thelatches 465, the latches 465 slide into the groove 498 to hold thesterile barrier assembly 422 onto the first mounting portion 424.Progressive engagement of the first catch 488 by the first pair oflatches 465 is shown in FIGS. 38 and 39.

This latch/catch arrangement allows the interface 460 to engage thefirst mounting portion 424 without requiring any tilting therebetween.In other words, the interface 460 can be pressed into engagement withthe first mounting portion 424 by solely longitudinal or linear movementof the interface 460.

Referring to FIGS. 40 and 41, with the interface 460 supported by thefirst mounting portion 424, the end effector EE is now able to engagethe interface 460. A second catch 483, similarly shaped to the firstcatch 488 is located to easily engage a second pair of latches 506 fixedto the second mounting portion 426. Operation and function of the secondcatch 483 and the second pair of latches 506 is similar to the firstcatch 488 and the first pair of latches 465 and will not be described indetail, but is progressively shown in FIGS. 40 and 41. The secondmounting portion 426, which is attached to the end effector EE, issimply pressed onto the interface 460 until the second catch 483 engagesthe second pair of latches 506, as shown in FIG. 41. Now the mountingsystem is ready to be preloaded and prepared for use. In this state, themounting system acts as a support mechanism to support the end effectorEE on the robotic arm R prior to preloading.

Referring to FIGS. 36 and 42-45, a preloading mechanism 486 clamps themounting portions 424, 426 together in position once they are broughttogether in approximate final orientation. A preloading element islocated in the interface 460. In this embodiment, the preloading elementis an elongated load member 480. The load member 480 is movablysupported in the interface 460. The load member 480 has first and secondends. The load member 480 may be formed of stainless steel, Kevlarcomposite, or other suitably rigid materials. The load member 480comprises a flange 482 near one end and the second catch 483 adjacentthe opposite end.

A preload force is applied to the load member 480. The preload force issized to exceed anticipated loading through the kinematic coupling sothat the kinematic coupling and associated properties are maintained.

The load member 480 is movably captured between the cover 469 and theback plate assembly 459. In particular, the load member 480 is able tomove from an unloaded position to a loaded position relative to thecover 469 and the back plate assembly 459. In the unloaded position, thesecond catch 483 is able to engage the second pair of latches 506. Inthe loaded position, the load member 480 is urged toward the back plateassembly 459 to load the mounting system.

Guide blocks 455 interconnect a cover plate 453 and the latch bracket464. More specifically, the guide blocks 455 define bores through whichfasteners pass to engage the latch bracket 464. The guide blocks 455 arearranged to space the cover plate 453 from the latch bracket 464. As aresult, an internal space is provided in the interface 460 in which theload member 480 can be moved during preloading.

The preloading mechanism 486 further includes a spring plate 505 and aconical disc spring 550, such as a Belleville spring, disposed betweenthe flange 482 of the load member 480 and the spring plate 505. Thespring plate 505 defines a first opening 511 (see FIG. 42) that is sizedto receive the load member 480. The disc spring 550 defines a secondopening 513 that is also sized to receive the load member 480. Asnap-ring secures the spring plate 505 and disc spring 550 to the loadmember 480.

The preloading mechanism 486 also includes a tensioner configured to,when actuated, urge the load member 480 toward the back plate assembly459 to load the mounting system. The tensioner includes a cam shaft 528supported for rotation relative to the cover 469 (see FIG. 44). Thetensioner also includes a pair of tensioning members 551 (also referredto as lifters). The tensioning members 551 are located between the coverplate 453 and the spring plate 505. The cover plate 453 is fastened tothe latch bracket 464 via fasteners.

The cam shaft 528 is supported for rotation by the guide blocks 455. Asa result, the cam shaft 528 is able to rotate between tensioned anduntensioned positions. The cam shaft 528 includes a pair of cam sections540 separated by a middle cylindrical section 536. The cylindricalsection 536 of the cam shaft 528 has a smaller diameter than the camsections 540. The cam sections 540 create a camming action as the camshaft 528 is rotated.

As shown in FIG. 45, the tensioning members 551 (two in the embodimentshown) have first ends engaged by the cam shaft 528 and second ends thatengage the spring plate 505. The second ends have rounded engagementsections 557 that sit in grooves 559 in the spring plate 505. As the camshaft 528 is rotated about a pivot axis P1, the tensioning members 551pivot about a pivot axis P2 while abutting the cover plate 453. Thisaction pivots their second ends into the spring plate 505 to urge thespring plate 505 away from the cover plate 453. Owing to the rigidconnection of the cover plate 453 to the latch bracket 464 and the latchbracket 464 to the back cover plate 467, the load member 480 movestoward the first catch 488 (which draws the second catch 483 toward thefirst catch 488), thereby providing the preloading needed to suitablysecure the end effector EE to the robot arm R.

As shown in FIGS. 44 and 45, the tensioner also includes a lever 546rotatably fixed to the cam shaft 528. The lever 546 may be rotatablyfixed to the cam shaft 528 through various types of engagements, e.g., aD-shaped bore to receive a D-shaped portion of the cam shaft 528, acoupler with geometric features so that the cam shaft 528 rotates as thelever 546 is rotated, etc. In the embodiment shown, a fastener (notnumbered) secures the lever 546 to the cam shaft 528 via a coupler. Thecam shaft 528 is rotated at least ninety degrees to move between theunloaded and loaded positions. Of course, other positions therebetweenmay place tension on the load member 480 and could be suitable forapplying the desired preload force.

The lever 546 may be locked when the cam shaft 528 is placed in thedesired position, e.g., the tensioned position. In the tensionedposition, the preload tensile force is applied to the load member 480.By locking the lever 546 after applying the preload force, the preloadforce is continually applied during use of the robotic arm R and endeffector EE to maintain the kinematic coupling. The preloading mechanism486 transfers the preload force across the sterile barrier assembly 422without piercing the barrier.

The tensioner applies the preload force to the load member 480 throughthe disc spring 550. The disc spring 550 applies a force equal to thepreload force to the load member 480. The disc spring 550 acts betweenthe spring plate 505 and the flange 482 of the load member 480. Inparticular, as the lever 546 is rotated, the cam shaft 528 rotates andthe cam sections 540 pivot the tensioning members 551 about the pivotaxis P2, and by extension, the spring plate 505 moves longitudinallyaway from the second catch 483 (which is engaging the second pair oflatches 506). The movement of the spring plate 505 compresses the discspring 550 and applies the preload force onto the load member 480 viathe flange 482.

Since the balls 428 are already generally aligned with the receptacles432, 438 before preloading, once the preload force is applied, the balls428 become seated in the receptacles 432, 438. Once seated, positions ofthe balls 428 are fixed and the positions of the receptacles 432, 438are fixed relative to one another. As a result, the mounting portions424, 426 are kinematically coupled together without piercing the sterilebarrier assembly 422.

Actuators, such as the push-button actuator 501 shown in FIG. 46, areused to manually separate the latches 465, 506 and release the catches488, 483 so that the end effector EE can be removed from the interface460 and the interface 460 can be removed from the robot arm R. Only theactuator 501 used to separate the first pair of latches 465 and releasethe first catch 488 will be shown and described in detail.

In the embodiment shown, the actuator 501 has a push button 560 fixed toa release frame 561. The release frame 561 is arranged with angledengagement surfaces 562 that engage pins 563 fixed to each of the firstpair of latches 465. The pins 563 extend away from the latches 465 intoopenings 564 in the release frame 561. The openings 564 are partiallydefined by the angled engagement surfaces 562. The pins 563 extend oneither side of the latch bracket 464 (see FIG. 46) so that the latches465 are guided to move along the latch bracket 464 via the pins 563.

In a normal, unactuated state, the pins 563, by virtue of the latches465 being biased toward one another by the biasing members B, are seatedand constrained at one end of the openings 564. The actuator 501 can beactuated by pressing the push button 560, which moves the release frame561 laterally across the latches 465, as shown by the arrow A1. Therelease frame 561 is constrained to this lateral motion by beingcaptured in a slide pocket in the latch bracket 464. Owing to thislateral motion of the release frame 561 and the latches 465 beingconstrained from similar lateral movement by the pins 563, the angledsurfaces 562 urge the pins 563 of each of the latches 465 away from eachother, thereby separating the latches 465 in the direction shown byarrows A2 against the bias of the biasing members B. As a result, thelatches 465 are disengaged from the first catch 488 (not shown in FIG.46) and the interface 460 can be removed from the first mounting portion424.

FIGS. 38-41 shows electrical power and other signal connections that canbe made through the sterile barrier assembly 422. In this embodiment,the interface 460 includes a plurality of electrical terminals embeddedin a carrier 600 disposed centrally in the cover 469. In thisembodiment, the electrical terminals are pins 478 that may be insertmolded into the carrier 600 of the interface 460. The pins 478 transferelectrical power/signals across the sterile barrier assembly 422. Thesepins 478 electrically interconnect electrical connectors 451, 457attached to the mounting portions 424, 426.

In this embodiment, the first mounting portion 424 includes the firstelectrical connector 451. The second mounting portion 426 includes thesecond electrical connector 457. When the mounting portions 424, 426 arecoupled together and preloaded, the electrical connectors 451, 457receive the pins 478 so that power and other electrical signals can flowthrough the pins 478. Thus, power, communication signals, or othersignals can be passed from the robotic arm R to the end effector EE andvice versa. The electrical connectors 451, 457 can be keyed to thecarrier 600 via a key/channel type interface or can be properly orientedby any suitable feature.

In the embodiment shown, the carrier 600 comprises a flange 602 (seeFIG. 43) and a cylindrical body 604 extending from the flange 602 tosupport the pins 478. The cylindrical body 604 is sized to fit within acylindrical passage through the load member 480. A wave spring 606 islocated between the flange 602 of the carrier 600 and the flange 482 ofthe load member 480. The wave spring 606 helps to maintain a position ofthe carrier 600 with respect to the electrical connectors 451, 457,i.e., by preventing movement of the carrier 600 when the load member 480moves to the unloaded position, which might otherwise occur due tofrictional engagement between the cylindrical body 604 in thecylindrical passage of the load member 480. The wave spring 606 alsoassists in returning the load member 480 to its unloaded position toengage the end effector EE. The wave spring 606 is also used to keep thetensioning members 551 in grooves in the cover plate 453 and in thegrooves 559 in the spring plate 505.

Referring to FIGS. 47A and 47B, the back ring plate 461 of the interface460 further includes gross alignment features for aligning the interface460 with the first mounting portion 424. In particular, the firstmounting portion 424 defines corresponding mating features for receivingthe alignment features. In the embodiment shown, the alignment featurescomprise posts 700, 702 extending rearwardly from a rear surface of theback ring plate 461 to engage openings 704, 706 in the first mountingportion 424. The posts 700, 702 include a first pair of posts 700 and asecond pair of posts 702 arranged on the back ring plate 461 oppositethe first pair of posts 700. The first pair of posts 700 are aligned ina plane, while the second pair of posts 702 are angled relative to oneanother, e.g., they are misaligned. The second pair of posts 702 arealso wider than the first pair of posts 700.

The openings 704, 706 comprise a first pair of openings 704 sized andshaped to receive the first pair of posts 700 and a second pair ofopenings 706 sized and shaped to receive the second pair of posts 702.The openings 704, 706 are sized and spaced to receive the respectiveposts 700, 702 with a small tolerance, e.g., to facilitate grosspositioning. Still, the second pair of posts 702 are sized so that theyare unable to fit in the first pair of openings 704 and the first pairof posts 700 are aligned so that they are unable to fit in the secondpair of openings 706. Owing to the spacing/arrangement of the posts 700,702 and the openings 704, 706, the interface 460 is only able to begrossly fitted onto the first mounting portion 424 in one orientation.The gross positioning also helps to align the electrical connectionsdescribed above prior to fully engaging the first catch 488 with thelatches 465.

When the balls 28, 228, 428 are made of an electrically insulatingmaterial such as ceramic, the sterile barrier assembly 22, 222, 422 canbe used as the electrical isolation needed to comply with electricalsafety requirements.

The balls 28, 228, 428 may provide three electrical contacts orterminals if they are made of a conductive material. In such a case, thesterile barrier assembly 22, 222, 422 could still be used as theelectrical isolation if the interfacing feature of the kinematiccoupling is made out of electrically insulating material.

One or more of the balls 28, 228, 428 may have optically transparentportions defined therethrough for transmitting data. The opticallytransparent portions may include throughbores filled with transparentplastic material or other material to maintain the barrier.

The kinematic couplers may have spherical and/or cylindrical segments inother embodiments.

The first mounting portion 24, 224, 424 may be a separate part that isrigidly connected to linkage L1 of the robotic arm R. The secondmounting portion 26, 226, 426 may be a separate part that is rigidlyconnected to a handpiece H of the end effector EE. In other embodiments,the first mounting portion 24, 224, 424 may be integrated into the oneor more linkages of the robotic arm R and the second mounting portion26, 226, 426 may be integrated into the handpiece of the end effectorEE. The mounting portions 24, 224, 424, 26, 226, 426 may be formed ofhardened steel, stainless steel or other rigid materials.

The robotic arm R may move the end effector EE in one or more degrees offreedom, including five or six degrees of freedom. The end effector EEmay include a surgical tool for milling tissue such as a milling bur formilling bone to receive an implant.

Examples of a robotic arm and end effector that can be outfitted withthe first and second mounting portions 24, 224, 424, 26, 226, 426 aredescribed in U.S. patent application Ser. No. 13/958,070, filed on Aug.2, 2013, entitled, “Surgical Manipulator Capable of Controlling aSurgical Instrument in Multiple Modes”, hereby incorporated byreference.

The first plurality of receptacles may include three V-groovedreceptacles. The three balls 28, 228, 428 would then self-center intothree V-shaped grooves of the three V-grooved receptacles so that eachball 28, 228, 428 is contacting two surfaces of the V-shaped grooves attwo contact points. As a result, the balls 28, 228, 428 make contactwith the three V-grooved receptacles at a total of six contact points toconstrain six degrees of freedom, i.e., each V-shaped groove constrainstwo degrees of freedom, thereby determinately orienting all six degreesof freedom between the first and second mounting portions. The first andsecond mounting portions are then clamped in this position with thepreloading mechanism as previously described.

The first plurality of receptacles and the second plurality ofreceptacles may each include three V-grooved or gothic arch shapedreceptacles so that exactly six contact points are made between contactsurfaces of the first plurality of receptacles and the kinematiccouplers and between contact surfaces of the second plurality ofreceptacles and the kinematic couplers.

The cone receptacles may be simplified by being replaced with threeblocks having planar surfaces circumferentially equally spaced from oneanother and arranged at an angle approximating the cone angle. In thisembodiment, the ball 28, 228, 428 seats within the three planar surfacesjust like being seated in the cone, but contact is made at three contactpoints with the three planar surfaces.

One or more of the first plurality of receptacles and/or the secondplurality of receptacles may comprise magnets to magnetically engage theballs in the receptacles. For instance, the first plurality ofreceptacles may comprise magnets to hold the balls to the first mountingportion until the second mounting portion is clamped to the firstmounting portion. Similarly, the first mounting portion, having thecontact surfaces of the receptacles integrated therein for kinematiccoupling, could comprise magnets to hold the balls against the contactsurfaces in the first mounting portion until the second mounting portionengages the first mounting portion.

The sterile barrier assembly 22, 222, 422 may be disposable. In otherembodiments, the interface 60, 260, 460 may comprise a separate fieldsterilizable assembly and can be re-usable. In this version, only thedrape 62, 262, 462 is disposable. In that case, there could be anadhesive tape, elastic seal, snap-ring, or mechanical clamping area ofthe drape 62, 262, 462 to seal to the interface 60, 260, 460 or featurescould be designed on the interface 60, 260, 460 to seal/clamp onto thedrape 62, 262, 462. Forming the balls 28, 228, 428 out of hard ceramicsuch as silicon carbide may minimize wear issues associated with reusingthe balls 28, 228, 428.

The protective covering 58, 258, 458 may include the drape 62, 262, 462without the interface 60, 260, 460 in which case the balls 28, 228, 428would be placed in openings in the drape 62, 262, 462 with the drape 62,262, 462 being sealed to the balls 28, 228, 428. In other words, theballs 28, 228, 428 would be integrated into the drape 62, 262, 462directly. In this instance, the robotic arm R could be configured toposition the first plurality of receptacles 30, 32, 34, 230, 232, 234,432 so that they lie in a generally horizontal plane so that the balls28, 228, 428 can be placed in the first plurality of receptacles 30, 32,34, 230, 232, 234, 432 and held there by gravity until installation ofthe sterile barrier assembly is complete.

Additional elastic straps or bungee cords may be attached to theinterface and configured to releasably engage posts or other features onthe first mounting portion to further initially support the sterilebarrier assembly when initially attaching the sterile barrier assemblyto the first mounting portion, e.g., after inserting the load bar 80into the load bar slot 104 of the receiver 100.

Several embodiments have been discussed in the foregoing description.However, the embodiments discussed herein are not intended to beexhaustive or limit the invention to any particular form. Theterminology which has been used is intended to be in the nature of wordsof description rather than of limitation. Many modifications andvariations are possible in light of the above teachings and theinvention may be practiced otherwise than as specifically described.

What is claimed is:
 1. A sterile barrier assembly for establishing abarrier between first and second surgical components, said sterilebarrier assembly comprising: a protective covering having a plurality ofkinematic couplers configured to provide a kinematic coupling betweenthe first and second surgical components through said protectivecovering to constrain exactly six degrees of freedom of movement betweenthe surgical components.
 2. The sterile barrier assembly of claim 1,further being coupled to: a first mounting portion associated with thefirst surgical component; a second mounting portion associated with thesecond surgical component; and wherein the plurality of kinematiccouplers are further configured to engage the mounting portions and toprovide the kinematic coupling between the mounting portions through theprotective covering to constrain six degrees of freedom of movementbetween the surgical components.
 3. The sterile barrier assembly ofclaim 2 including a preloading mechanism having a preloading element,said preloading mechanism configured to clamp said mounting portionstogether through said protective covering.
 4. The sterile barrierassembly of claim 3 wherein said preloading mechanism includes atensioner operatively coupled to said preloading element for tensioningsaid preloading element and clamping said mounting portions together. 5.The sterile barrier assembly of claim 4 wherein said tensioner includesa cam shaft and a lever rotatably fixed to said cam shaft, said camshaft rotatable between tensioned and untensioned positions.
 6. Thesterile barrier assembly of claim 3 wherein said preloading elementincludes a load member.
 7. The sterile barrier assembly of claim 3wherein said preloading mechanism includes one of a first catch or afirst latch associated with said first mounting portion and one of asecond catch or a second latch associated with said second mountingportion.
 8. The sterile barrier assembly of claim 2 wherein said firstmounting portion includes a first plurality of contact surfaces forengaging said plurality of kinematic couplers and said second mountingportion includes a second plurality of contact surfaces for engagingsaid plurality of kinematic couplers, said contact surfaces shaped tocooperate with said plurality of kinematic couplers to constrain the sixdegrees of freedom of movement between the surgical components.
 9. Thesterile barrier assembly of claim 8 wherein said first mounting portionincludes a first plurality of receptacles having said first plurality ofcontact surfaces and said second mounting portion includes a secondplurality of receptacles having said second plurality of contactsurfaces.
 10. The sterile barrier assembly of claim 8 wherein said firstplurality of contact surfaces are configured to provide only six contactpoints with said plurality of kinematic couplers.
 11. The sterilebarrier assembly of claim 8 wherein each of said second plurality ofcontact surfaces have conical configurations.
 12. The sterile barrierassembly of claim 2 including a support mechanism for supporting saidprotective covering on said first mounting portion when coupling thefirst and second surgical components.
 13. The sterile barrier assemblyof any of claim 2, wherein said first mounting portion is associatedwith a robotic arm and said second mounting portion is associated withan end effector.
 14. The sterile barrier assembly of claim 1 whereinsaid protective covering includes an interface and a drape attached tosaid interface, said interface including said plurality of kinematiccouplers integrated therein.
 15. The sterile barrier assembly of claim14 wherein each of said plurality of kinematic couplers are arranged tolaterally move relative to one another.
 16. The sterile barrier assemblyof claim 14 wherein said interface includes a preloading element forpreloading the kinematic coupling between the surgical components. 17.The sterile barrier assembly of claim 14 wherein said interface includesa plurality of electrical terminals.
 18. The sterile barrier assembly ofclaim 14 wherein said drape comprises a ring defining an opening forreceiving said interface and a flaccid portion attached to said ring.19. The sterile barrier assembly of claim 14 wherein said protectivecovering includes a support member for supporting said protectivecovering on the first surgical component during installation on thefirst surgical component.
 20. The sterile barrier assembly of claim 14wherein said interface comprises at least one of a first latch or afirst catch for engaging the first surgical component and at least oneof a second latch or a second catch for engaging the second surgicalcomponent.
 21. The sterile barrier assembly of claim 14 wherein saidplurality of kinematic couplers are further defined as a plurality ofballs.
 22. The sterile barrier assembly of claim 21 wherein saidplurality of balls are further defined as three balls configured toconstrain the six degrees of freedom of movement between the surgicalcomponents.
 23. The sterile barrier assembly of claim 21 wherein saidballs comprise ceramic.
 24. The sterile barrier assembly of claim 21wherein said balls comprise at least one of silicon carbide or tungstencarbide.
 25. The sterile barrier assembly of claim 21 wherein said ballscomprise steel.
 26. The sterile barrier assembly of claim 21 wherein oneor more of said plurality of balls have optically transparent portionsfor transmitting data.
 27. A method for coupling the first and secondsurgical components with the sterile barrier assembly of claim 1, saidmethod comprising the steps of: placing the sterile barrier assembly onthe first surgical component; placing the second surgical component onthe sterile barrier assembly; and preloading a preloading element tokinematically couple the surgical components together through thesterile barrier assembly with the plurality of kinematic couplers.
 28. Asterile barrier assembly for establishing a barrier between first andsecond surgical components, said sterile barrier assembly comprising: aprotective covering including: an interface having a plurality ofkinematic couplers integrated therein configured to provide a kinematiccoupling between the first and second surgical components through saidprotective covering to constrain six degrees of freedom of movementbetween the surgical components, wherein each of said plurality ofkinematic couplers are arranged to laterally move relative to oneanother; and a drape attachable to said interface.
 29. A sterile barrierassembly for establishing a barrier between first and second surgicalcomponents, said sterile barrier assembly comprising: a protectivecovering including: an interface having a plurality of kinematiccouplers integrated therein configured to provide a kinematic couplingbetween the first and second surgical components through said protectivecovering to constrain six degrees of freedom of movement between thesurgical components, wherein said interface includes a preloadingelement for preloading the kinematic coupling between the surgicalcomponents; and a drape attachable to said interface.
 30. A sterilebarrier assembly for establishing a barrier between first and secondsurgical components, said sterile barrier assembly comprising: aprotective covering including: an interface having a plurality ofkinematic couplers integrated therein configured to provide a kinematiccoupling between the first and second surgical components through saidprotective covering to constrain six degrees of freedom of movementbetween the surgical components; and a drape attachable to saidinterface and comprising a ring defining an opening for receiving saidinterface and a flaccid portion attached to said ring.
 31. A sterilebarrier assembly for establishing a barrier between first and secondsurgical components, the first surgical component comprising a firstmounting portion and the second surgical component comprising a secondmounting portion, said sterile barrier assembly comprising: a protectivecovering having a plurality of kinematic couplers configured to engagethe mounting portions and to provide the kinematic coupling between themounting portions through said protective covering to constrain sixdegrees of freedom of movement between the surgical components.